Andrew M Butler, ed: An Unofficial Companion to the Novels of Terry Pratchett

Not so much a companion as a small illustrated encyclopedia, this reference book anatomises Terry Pratchett's works (not only novels, despite what the title says) and their spinoffs in over 250 essays – some long, some short. Butler, who was a co-editor of Terry Pratchett: Guilty of Literature, classifies his entries under 21 headings from Adaptations, Bromeliad and Characters to Species, Themes and White Knowledge.

That last one is a neat phrase for "what everybody knows", the way 1066 And All That (whose authors get an entry) is "all the history you can remember." Discworld versions of Ancient Egypt, Australia and China/Japan are manic remixes of all our muddled folklore about those places. Besides obligatory essays on the books, characters or locations, Butler and his contributors cast a wide net to probe Pratchett's sources, influences and esoteric allusions. Thus there are entries for Cats, Gormenghast, Libraries, Trousers of Time, Widdershins and much more.

Though more scholarly than The Discworld Companion, the Unofficial Companion is easy reading and crammed with interesting nuggets. Not just for completists but for anyone who's tempted to ponder what makes Terry Pratchett tick.

Things We Learned, from the Elephants entry: "The name 'elephant' refers to a large, herbivorous pachyderm mammal, with a long proboscis and large ears." Mr Butler is full of these little surprises.

Sheri S. Tepper: The Margarets

Sheri S Tepper has the knack of telling fairy stories with an ambitious SF background. Not corny "Puss in Boots on Mars" reworkings – though there's a race of intelligent and sympathetic cats here – but new moral fables with the mythic ring of very old ones.

Her plot has deep roots, beginning in Earth's prehistory when some hapless primitives offend an insanely touchy bunch of alien visitors. Revenge is taken, leaving our whole race mentally damaged. We're somehow unable to stop fouling the nest and ruining every world we live on. By the late 21st century, even our best galactic friends are planning extreme measures. For our own good.

Margaret is a human girl whose life mysteriously splits along many paths. Alternate Margarets become a wife, queen, male warrior, healer, linguist, spy, shaman ... all the roles she imagined for herself when little. Some of these lives are gruelling, especially when touched by the weird, unpleasant parasites created as an anti-human extinction weapon by enemies who – not content with messing us up in the first place – have nursed their grudge for over 50,000 years.

The various Margaret histories are shaped by gods, of a kind, as part of an age-old plan to fulfil the prophecy hidden in a folktale. This features one person's impossible task of walking seven roads at once. For roads, read galactic wormhole portals linking seven worlds where the seven Margarets have ended up. Not easy, but just barely possible ...

Tepper is an artful storyteller who makes you believe in technologies very close indeed to magic. Amid gruesome flashes of imagination, she has a heartfelt environmental message but is too old and wise (next year she'll be eighty) to lapse into preachiness. Her resonant future fables linger in the memory.

Tepper didn't start publishing novels until her mid-50s, with the quirky "True Game" science-fantasies that opened with King's Blood Four (1983) and gathered a cult following.

Stephen Hunt: The Kingdom Beyond the Waves

This follow-up to The Court of the Air is definitely a ripping yarn, an Indiana Jones romp through an alternate-Victorian steampunk world with warped laws of physics. Internal combustion and electronics don't work; instead there are steam-powered "transaction engine" computers and AI robots, plus much brass-knobbed retro technology like aerostats and bathyspheres. Magic, too, and new human subspecies with shells or wings. It's all richly detailed and reminiscent of China Mieville's New Crobuzon.

Archaeologist heroine Amelia seeks the legendary city-utopia of Camlantis, long lost in the sky. Bankrolled by a rich idealist who isn't revealing all his plans, Amelia and her motley submarine crew trek through jungle guarded by dinosaurs and ruled by a hive mind whose recruiting tactics make the Borg look wishy-washy. Beyond, maybe, lies the key to Camlantis. Crisis follows crisis; every chapter brings new horrors or betrayals. Hunt turns all the dials up to 11.

Meanwhile, a slightly insane Scarlet Pimpernel figure with a shifting face, a clockwork cyborg arm and a winged accomplice is freeing condemned aristocrats from a country very like post-revolutionary France. Then he's conned into liberating someone who should have been left to rot ...

As the story pounds along, the sheer number of split-second escapes from certain death – and fates worse than death – comes close to being absurd. Constant inventiveness keeps the reader hooked. Lost Camlantis itself could have been anticlimactic but contains dire secrets. No spoilers, now, but would you trust any social reformer with powers that could grant the old East German regime's favourite wish (at least according to Bertolt Brecht): to dissolve the population and elect another one?

The prolonged finale is a cracking succession of cliff-hangers and surprise comebacks. Great fun even if you don't believe a word of it. It would film well.

Despite the 19th-century feel, this seems to be the distant future. Another supposedly mythical metropolis was found "rotting under the ocean" ... the City of Lost Angels. Nudge, nudge. [SFX assumed its readers would be too stupid to grasp this, and cautiously added "Los Angeles". Oh dearie me.]

Vernor Vinge: The Collected Stories of Vernor Vinge

Vernor Vinge is a major SF author with four Hugo awards on his shelf. This collection, first published in America in 2001, tracks his career from its 1966 debut: "Bookworm, Run!", exploring the favourite Vinge theme of computer-enhanced intelligence. The experimental subject is a likable chimp who, with access to the totality of human knowledge, prefers to lounge around reading old SF novels until he realises that what he knows could be terribly dangerous ...

Vinge firmly believes in a coming "Technological Singularity" where brain and computer power are no longer distinct, and both soar off the scale of what we can now understand. Which makes post-Singularity stories tough to write. One solution is to imagine a war that slows or turns back the clock. Examples here include "The Ungoverned", featuring a fragmented, anarcho-libertarian America whose rugged individualists are free to stockpile all the household WMDs they can afford – even nukes. Don't tell George Bush.

Other stories like "The Barbarian Princess" feature superintelligent posthumans who are still immature, still comprehensible to us slobs. Vinge's cheekiest twist on Singularity is his Zones of Thought cosmos, where the limits of computing depend on galactic location: Earth is in the crippled Slow Zone, but out in the Beyond technology can truly approach magic. "The Blabber", opening story of this sequence, introduces the fascinatingly odd alien Tines who become important players in A Fire Upon the Deep. Another novel-linked story is "Fast Times at Fairmont High", set in the same glittering near-future California (trembling on the edge of Singularity but huge fun to live in) as the recent Rainbows End. What weird tech will tomorrow's kids consider as commonplace as mobile phones ... and what will they see as a challenging school project? Aha.

Vinge hasn't done badly as an SF prophet. "Bookworm" casually foretells the Soviet Union's economic collapse. His 1981 "True Names" – not included here, alas – got many things right about how hackers would use and misuse the coming internet. Another tale predicts that the future of cinema lies in computer animation, including an Oscar-winning CGI Lord of the Rings – quite visionary in 1967 when the only option was seriously expensive mainframe time. Of course such early insights seem less amazing now.

Reading the collection in sequence, you can see Vinge maturing from clever competence and slick storytelling to something rather special. His aliens keep getting deeper and more sympathetic – if that's the word for the appalling but intellectual cannibals of "Original Sin". There are forewords telling where each story came from, with touches of sometimes embarrassed hindsight. Entertaining throughout, with repeated shakes of the kaleidoscope to show cherished ideas in a different and dazzling light. Read and learn.

Arthur C Clarke (1917-2008)

"Overhead, without any fuss, the stars were going out." That famous Clarke punchline from "The Nine Billion Names of God" was remembered by countless fans when Sir Arthur died in Sri Lanka on 18 March. In the mid-20th century a whole constellation of authors had worked to make SF a grown-up literary genre: the brightest stars were Asimov, Heinlein and Clarke. He was the last of the three to go out, at the respectable age of 90.

Fame works in funny ways, and the three things for which Clarke became best known weren't his SF writing. A prediction: in his noted 1945 article for Wireless World, he proposed the geostationary communications satellite. An epigram: Clarke's Third Law – one of three guidelines for futurologists – "Any sufficiently advanced technology is indistinguishable from magic." A classic film: 2001: A Space Odyssey, inspired by but very different from his 1951 short "Sentinel of Eternity", later retitled "The Sentinel".

Clarke and Stanley Kubrick worked closely together on 2001, with the book version – not a simple film novelization – evolving along with the script. Both creators wanted to evoke cosmic awe, but Kubrick's film leaned towards chill mystery while Clarke's novel included both mysticism and lucid explanations.

The key to Clarke's appeal is that he was both a qualified scientist (not to mention a fine science writer) and a mystic who dreamed of infinity and eternity. One mentor was Olaf Stapledon, a pioneer explorer of deep time and far-future human evolution in Last and First Men and Star Maker. Another was the fantasy author and poet Lord Dunsany. All his life, Clarke tried to convey the poetry of space, time and stars – that special SF thrill called the sense of wonder.

His best novels? In The City and the Stars, the young hero is the only person in Earth's last city – unchanged for a billion years – to wonder what lies outside; prying leads to awesome revelations. Childhood's End deals with our evolutionary leap into transcendence, seen by the final human generation who can't understand what their children have become. Rendezvous With Rama, exploring a gigantic alien vessel that passes briefly through the Solar System, won Hugo and Nebula awards; so did The Fountains of Paradise, whose as yet unfulfilled prediction is the space elevator.

Clarke's first Hugo came in 1956 for "The Star", a grim story about the true nature of that guiding light over Bethlehem. He received the SF Writers of America Grand Master lifetime award in 1986, and as we all know was eventually knighted. From 1987 he generously funded the annual Clarke Award, with a hefty cash prize for the SF novel judged best each year.

It's tempting to think that Clarke's gravestone will take the notorious shape of a tall black monolith. Inscribed, perhaps, with the last words of a religious prophet in the immense back-story of The City and the Stars, reporting not a vision but a place he'd visited: "It is lovely to watch the coloured shadows on the planets of eternal light."

John C. Wright: Null-A Continuum

A E van Vogt's The World of Null-A and its sequel are cult classics of 1940s SF, both loved and hated for the cloudy dream-logic of their plots. The hero Gilbert Gosseyn is an amnesiac superman with an extra brain (or "extra-brain") and the power to teleport, who wakes in a new cloned body whenever killed. He's constantly manipulated by an unknown "cosmic chess-player" to oppose the galactic invasion of our solar system, but never learns why, nor who he actually is.

In this authorised sequel, John C Wright works hard to imitate van Vogt's clunky pulp-melodrama style and relentless pace, with a fresh development – or at least someone bursting in with a gun – roughly every 800 words. The retro technology is nostalgic, with vast atomic dynamo rooms, self-aiming gyroscopic pistols and lie detectors crammed with glowing vacuum tubes.

Wright isn't afraid to think big, and outdoes the pulp SF master. Planets get gobbled by the thousand. Besides familiar foes like van Vogt's wicked galactic emperor Enro the Red, there's a new and universe-sized menace against which Gosseyn's amazing feats – like hurling our entire galaxy across 2.9 million light-years – seem futile. Yes, Null-A Continuum is sometimes slightly tongue-in-cheek (wait for the bit where our hero teleports the Big Bang!) but everything hangs together and eventually makes a weird kind of sense.

Intergalactic travel, time travel, cyclic universes, false realities, unkillable villains, continuum-eaters ... all the props of grand space opera are chucked around with reckless abandon, up to and including the metacosmic kitchen sink. Wright deftly steers this whole lumbering farrago to the happy ending that was foreshadowed (though somehow avoided) in the first book. Recommended for van Vogt fans.

The World of Null-A is rated as a major SF classic in France – translated by the admired Surrealist author Boris Vian. Could it possibly have gained in translation?

Arthur C Clarke and Stephen Baxter: Firstborn

This "Time Odyssey" trilogy occupies a universe next door to the famous 2001: A Space Odyssey – not a sequel but, according to Clarke and Baxter, an "orthoquel". There are ancient, inscrutable aliens, the Firstborn, but now they're implacably hostile. Shiny spherical "Eyes" can do absolutely anything that a black monolith could. Man-apes make cameo appearances. Human-built AIs have their secrets, but unlike HAL are totally loyal.

The Firstborn disapprove of energy-hungry technological civilizations, like ours. In Time's Eye they played sadistically with us, creating a game-world named Mir that's a patchwork of historical eras, so Alexander the Great faced a final showdown with Genghis Khan. In Sunstorm they tried to sterilise Earth's biosphere with a massive solar eruption. Now they're really annoyed, and their devastating Q-bomb is making its leisurely way from Jupiter towards fatal impact with Earth. What to do?

Not a lot. Satirically echoing the War On Terror, humanity's futile defence policy is called the War With The Sky. Firstborn supertechnology is unstoppable, shrugging off our ultimate weapons with contemptuous ease. Meanwhile, though, series heroine Bisesa Dutt is smuggled to Mars, where – again recalling 2001 – researchers have uncovered an enigmatic buried artefact. This offers a gateway to the Mir solar system, which has a few surprises left ...

Like Baxter's solo novel Space, "A Time Odyssey" assumes a hugely dangerous universe. This final volume isn't the best: its logic seems a trifle wobbly, and the well-told story lacks focus until at last the Get Out Of Doomsday Free card is dealt from the bottom of the pack. But the finale includes a bracing touch of Baxterian chill. Solidly traditional SF.

"Gollancz's final novel from Sir Arthur C Clarke", the press release sadly begins. If style is any guide, though, collaborator Baxter did most (all?) of the actual writing.

Steven Erikson: Toll the Hounds

There's an old SF fan catchphrase that goes: "Death will not release you." That's a good motto for Steven Erikson's fantasy sequence "The Malazan Book of the Fallen", where some characters seem unkillable, or are dead but won't lie down, or find death is only the overture to something else.

This eighth volume is a tale of two cities. Darujhistan – introduced in book one, Gardens of the Moon – throbs with quirky sex, violence and intrigue. There are power struggles, family complications and an assassins' guild whose latest contract is a tough job indeed. Another city, Black Pearl, is shrouded in endless Night and ruled by an ancient whose Stormbringer-like sword contains a particularly nasty hell.

The accumulated back-story is now overwhelming. Several invincible warriors converge on Darujhistan, while there's obscure strife among gods and their ravening Hounds. A major god dies! All the dead come marching! The moon shatters! And much more. Erikson skilfully varies this high-fantasy action with bizarre humour, knowingly mannered descriptions, and deft characterisation. He has you genuinely hoping the nicer folk will survive. Many don't.

Fantasy cliches are dodged or given new twists; the narrative teems with clever invention. Alas, it also carries a fair amount of excess baggage: characters with later parts to play but no obvious function here. For example, one invincible warrior misses the big climax because someone deliberately, self-sacrificingly, delays him: what's he doing in this book at all? Similarly underused dragons, gods, and subplots are frustrating loose ends ... at least for now.

A well-crafted, engaging and ultimately exhausting instalment. The cursed undead within the sword Dragnipur must forever pull their hideous, crushing Burden. Maybe it's a 923-page book. All the same, the writing is excellent.

The Malazan saga began as a 1980s role-playing-game background, devised with Ian Cameron Esslemont. Erikson plans ten books in all, and Esslemont a related series of five. Gasp.

Brian Herbert & Kevin J Anderson: Paul of Dune

They're at it again! After eight Dune series prequels and sequels, Anderson and Herbert are hammering wedges into the cracks with interquels – first filling the long-standing and much-needed gap between Dune and Dune Messiah.

Paul Muad'Dib is now Emperor of the Galaxy, and his Fremen desert warriors are on an interstellar jihad to crush all opposition, mainly by sword-fighting. Bad things happen. Paul tells himself, rather frequently, that the ends justify the means.

Meanwhile there are flashbacks. Though it's made clear in Dune that fifteen-year-old Paul had never before left his home planet, the latest retcon features an offworld trip when he was twelve. Lots of action, booby-traps, and flamboyant villains including – yet again – the fatso from hell, Baron Vladimir Harkonnen.

Unfortunately the original Dune and Dune Messiah are loaded with spoilers for all this galactic thud-and-blunder. We know who must survive; it doesn't take Paul's gift of prophecy to guess that major new characters will be killed off. At least they're disposed of in lively and inventive ways, including an infernal machine that wouldn't get through today's airport security but passes unnoticed in this intensely paranoid future where assassins are commonplace.

The increased super powers granted by special Bene Gesserit training are also getting hard to believe. For example: fifteen heavily armed warriors expecting attack are quickly destroyed by a girl aged six. Using only a small dagger, and her bare hands. In the dark.

As lightweight space opera, Paul of Dune is entertaining enough. The pages turn easily. But the unique spice-flavour of Frank Herbert's creation has become diluted almost beyond recognition. For dogged completists with ample shelf space.

The plan is to fill the 12-year interval between books with a trilogy. How many trilogies, do you think, for the 3,500 years between Children of Dune and God-Emperor of Dune?